The practice of too frequently using the word I; hence, a speaking or writing overmuch of one's self; self-exaltation; self-praise; the act or practice of magnifying one's self or parading one's own doings. The word is also used in the sense of egoism.

an exaggerated opinion of your own importance

the practice of talking about oneself too much; an exaggerated sense of self importance.

Egotism is a character trait which describes a person who acts to gain values in an amount greater than that of the values he/she gives to others. This is usually accomplished by exploiting the altruism, irrationality, or ignorance of others — or by using coercive force and/or fraud.

an inflated feeling of pride in your superiority to others